Novel research approaches for interstitial cystitis/bladder pain syndrome: thinking beyond the bladder
Despite years of basic and clinical research focused on interstitial cystitis/bladder pain syndrome (IC/BPS), including clinical trials of candidate therapies, there remains an insufficient understanding of underlying cause(s), important clinical features and a lack of effective treatments for this syndrome. Progress has been limited and is likely due to many factors, including a primary focus on the bladder and lower urinary tract as origin of symptoms without adequately considering the potential influence of other local (pelvic) or systemic factors. Traditionally, there has been a lack of sufficiently diverse expertise and application of novel, integrated methods to study this syndrome. However, some important insights have been gained. For example, epidemiological studies have revealed that IC/BPS is commonly associated with other chronic pain conditions, including fibromyalgia, irritable bowel syndrome and chronic fatigue syndrome. These observations suggest that IC/BPS may involve systemic pathophysiology, including alterations of the central nervous system in some patients. Furthermore, there may be multiple causes and contributing factors that manifest in the symptoms of IC/BPS leading to multiple patient sub-groups or phenotypes. Innovative research is necessary to allow for a more complete description of the relationship between this syndrome and other disorders with overlapping symptoms. This report provides examples of such innovative research studies and their findings which have the potential to provide fresh insights into IC/BPS and disorders associated with chronic pain through characterization of broad physiologic systems, as well as assessment of the contribution of the bladder and lower urinary tract. They may also serve as models for future investigation of symptom-based urologic and non-urologic disorders that may remain incompletely characterized by previous, more traditional research approaches. Furthermore, it is anticipated a more holistic understanding of chronic urologic pain and dysfunction will ensue from productive interactions between IC/BPS studies like those described here and broader cutting-edge research endeavors focused on potentially related chronic pain disorders. A more comprehensive vision for IC/BPS inquiry is anticipated to yield new insights into basic disease mechanisms and clinical characteristics that will inform future research studies that will lead to more effective therapies and improved clinical care for these patients.